From ffec80a04d430e84b7aaf8dd571a611538a711f1 Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Thu, 26 Jun 2025 19:20:31 +0530
Subject: [PATCH 1/9] $file.readBuffer to read the data from disk

---
 demo/node/rntuple_test.js |  5 +++--
 modules/rntuple.mjs       | 36 ++++++++++++++++++++++++++++++++++--
 2 files changed, 37 insertions(+), 4 deletions(-)

diff --git a/demo/node/rntuple_test.js b/demo/node/rntuple_test.js
index a16a02c42..67fe2190c 100644
--- a/demo/node/rntuple_test.js
+++ b/demo/node/rntuple_test.js
@@ -4,10 +4,11 @@ import { readHeaderFooter } from 'jsroot/rntuple';
 
 
 console.log(`JSROOT version ${version}`);
+// let file = await openFile('https://jsroot.gsi.de/files/tmp/ntpl001_staff.root');
 
-let file = await openFile('https://jsroot.gsi.de/files/tmp/ntpl001_staff.root');
+let file = await openFile('./simple.root');
 
-let rntuple = await file.readObject('Staff');
+let rntuple = await file.readObject('myNtuple');
 
 await readHeaderFooter(rntuple);
 
diff --git a/modules/rntuple.mjs b/modules/rntuple.mjs
index 9d82bfc00..ee19f1b25 100644
--- a/modules/rntuple.mjs
+++ b/modules/rntuple.mjs
@@ -495,6 +495,15 @@ const numRecordCluster = reader.readU32();
 
   this.pageLocations = clusterPageLocations;
 }
+deserializePage(blob) {
+  const reader = new RBufferReader(blob);
+  console.log('Deserializing first 10 double values from data page ')
+  for (let i = 0; i < 10; ++i) {
+    const val = reader.readF64();
+    console.log(val);
+  }
+}
+
 
 }
 
@@ -527,7 +536,7 @@ async function readHeaderFooter(tuple) {
          tuple.builder.deserializeHeader(header_blob);
 
          tuple.builder.deserializeFooter(footer_blob);
-
+        // Deserialize the Page List Envelope
          const group = tuple.builder.clusterGroups?.[0];
          if (!group || !group.pageListLocator)
             throw new Error('No valid cluster group or page list locator found');
@@ -545,7 +554,30 @@ async function readHeaderFooter(tuple) {
                   throw new Error(`Unzipped page list is not a DataView, got ${Object.prototype.toString.call(unzipped_blob)}`);
 
                tuple.builder.deserializePageList(unzipped_blob);
-               return true;
+
+               // Read the first page data
+               const firstPage = tuple.builder?.pageLocations?.[0]?.[0]?.pages?.[0];
+               if (!firstPage || !firstPage.locator)
+                  throw new Error('No valid first page found in pageLocations');
+
+               const pageOffset = Number(firstPage.locator.offset),
+                     pageSize = Number(firstPage.locator.size),
+                     uncompressedPageSize = 8000; 
+                                  console.log('Compressed size :', pageSize);
+
+               return tuple.$file.readBuffer([pageOffset, pageSize]).then(compressedPage => {
+                  if (!(compressedPage instanceof DataView))
+                     throw new Error('Compressed page readBuffer did not return a DataView');
+
+                  return R__unzip(compressedPage, uncompressedPageSize).then(unzippedPage => {
+                     if (!(unzippedPage instanceof DataView))
+                        throw new Error('Unzipped page is not a DataView');
+
+                     tuple.builder.deserializePage(unzippedPage);
+
+                     return true;
+                  });
+                });
             });
          });
       });

From f6dfc7b4f680febcd7e6ecb4f30590ff6b8dc8d7 Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Fri, 27 Jun 2025 13:55:33 +0530
Subject: [PATCH 2/9] Added rntuple_test.jsin .yml

---
 .github/workflows/jsroot-ci.yml |  4 +++
 demo/node/rntuple_test.js       |  7 +++--
 modules/rntuple.mjs             | 53 +++++++++++++++++----------------
 3 files changed, 36 insertions(+), 28 deletions(-)

diff --git a/.github/workflows/jsroot-ci.yml b/.github/workflows/jsroot-ci.yml
index e6a394eda..91248eeb4 100644
--- a/.github/workflows/jsroot-ci.yml
+++ b/.github/workflows/jsroot-ci.yml
@@ -63,6 +63,7 @@ jobs:
           node demo/node/file_proxy.js multi ./hsimple.root
           node demo/node/file_proxy.js buffer ./hsimple.root
           node demo/node/buffer_test.js
+          node demo/node/rntuple_test.js
 
   tests_ubuntu:
     runs-on: ubuntu-latest
@@ -176,6 +177,8 @@ jobs:
           node demo/node/file_proxy.js multi ./hsimple.root
           node demo/node/file_proxy.js buffer ./hsimple.root
           node demo/node/buffer_test.js
+          node demo/node/rntuple_test.js
+
 
   build-windows:
     runs-on: windows-latest
@@ -223,4 +226,5 @@ jobs:
           node demo/node/file_proxy.js multi ./hsimple.root
           node demo/node/file_proxy.js buffer ./hsimple.root
           node demo/node/buffer_test.js
+          node demo/node/rntuple_test.js
 
diff --git a/demo/node/rntuple_test.js b/demo/node/rntuple_test.js
index 67fe2190c..1a78cab6a 100644
--- a/demo/node/rntuple_test.js
+++ b/demo/node/rntuple_test.js
@@ -4,11 +4,12 @@ import { readHeaderFooter } from 'jsroot/rntuple';
 
 
 console.log(`JSROOT version ${version}`);
-// let file = await openFile('https://jsroot.gsi.de/files/tmp/ntpl001_staff.root');
+const file = await openFile('https://jsroot.gsi.de/files/tmp/ntpl001_staff.root'),
+rntuple = await file.readObject('Staff');
 
-let file = await openFile('./simple.root');
+// let file = await openFile('./simple.root');
 
-let rntuple = await file.readObject('myNtuple');
+// let rntuple = await file.readObject('myNtuple');
 
 await readHeaderFooter(rntuple);
 
diff --git a/modules/rntuple.mjs b/modules/rntuple.mjs
index ee19f1b25..ee8f4362c 100644
--- a/modules/rntuple.mjs
+++ b/modules/rntuple.mjs
@@ -495,14 +495,16 @@ const numRecordCluster = reader.readU32();
 
   this.pageLocations = clusterPageLocations;
 }
-deserializePage(blob) {
-  const reader = new RBufferReader(blob);
-  console.log('Deserializing first 10 double values from data page ')
-  for (let i = 0; i < 10; ++i) {
-    const val = reader.readF64();
-    console.log(val);
-  }
-}
+
+// Example Of Deserializing Page Content
+// deserializePage(blob) {
+//   const reader = new RBufferReader(blob);
+//   console.log('Deserializing first 10 double values from data page ')
+//   for (let i = 0; i < 10; ++i) {
+//     const val = reader.readF64();
+//     console.log(val);
+//   }
+// }
 
 
 }
@@ -554,30 +556,31 @@ async function readHeaderFooter(tuple) {
                   throw new Error(`Unzipped page list is not a DataView, got ${Object.prototype.toString.call(unzipped_blob)}`);
 
                tuple.builder.deserializePageList(unzipped_blob);
+               return true;
 
                // Read the first page data
-               const firstPage = tuple.builder?.pageLocations?.[0]?.[0]?.pages?.[0];
-               if (!firstPage || !firstPage.locator)
-                  throw new Error('No valid first page found in pageLocations');
+              //  const firstPage = tuple.builder?.pageLocations?.[0]?.[0]?.pages?.[0];
+              //  if (!firstPage || !firstPage.locator)
+              //     throw new Error('No valid first page found in pageLocations');
 
-               const pageOffset = Number(firstPage.locator.offset),
-                     pageSize = Number(firstPage.locator.size),
-                     uncompressedPageSize = 8000; 
-                                  console.log('Compressed size :', pageSize);
+              //  const pageOffset = Number(firstPage.locator.offset),
+              //        pageSize = Number(firstPage.locator.size),
+              //        uncompressedPageSize = 8000; 
+              //                     console.log('Compressed size :', pageSize);
 
-               return tuple.$file.readBuffer([pageOffset, pageSize]).then(compressedPage => {
-                  if (!(compressedPage instanceof DataView))
-                     throw new Error('Compressed page readBuffer did not return a DataView');
+              //  return tuple.$file.readBuffer([pageOffset, pageSize]).then(compressedPage => {
+              //     if (!(compressedPage instanceof DataView))
+              //        throw new Error('Compressed page readBuffer did not return a DataView');
 
-                  return R__unzip(compressedPage, uncompressedPageSize).then(unzippedPage => {
-                     if (!(unzippedPage instanceof DataView))
-                        throw new Error('Unzipped page is not a DataView');
+              //     return R__unzip(compressedPage, uncompressedPageSize).then(unzippedPage => {
+              //        if (!(unzippedPage instanceof DataView))
+              //           throw new Error('Unzipped page is not a DataView');
 
-                     tuple.builder.deserializePage(unzippedPage);
+              //        tuple.builder.deserializePage(unzippedPage);
 
-                     return true;
-                  });
-                });
+              //        return true;
+              //     });
+              //   });
             });
          });
       });

From 14cdddbb4575bcf6bed84bba21b0ebb87c19e1ae Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Fri, 27 Jun 2025 15:50:11 +0530
Subject: [PATCH 3/9] Added the simple.root

---
 demo/node/rntuple_test.js |   8 ++++----
 demo/node/simple.root     | Bin 0 -> 8511 bytes
 2 files changed, 4 insertions(+), 4 deletions(-)
 create mode 100644 demo/node/simple.root

diff --git a/demo/node/rntuple_test.js b/demo/node/rntuple_test.js
index 1a78cab6a..9ac5792bd 100644
--- a/demo/node/rntuple_test.js
+++ b/demo/node/rntuple_test.js
@@ -4,12 +4,12 @@ import { readHeaderFooter } from 'jsroot/rntuple';
 
 
 console.log(`JSROOT version ${version}`);
-const file = await openFile('https://jsroot.gsi.de/files/tmp/ntpl001_staff.root'),
-rntuple = await file.readObject('Staff');
+// const file = await openFile('https://jsroot.gsi.de/files/tmp/ntpl001_staff.root'),
+// rntuple = await file.readObject('Staff');
 
-// let file = await openFile('./simple.root');
+const file = await openFile('./simple.root'),
 
-// let rntuple = await file.readObject('myNtuple');
+rntuple = await file.readObject('myNtuple');
 
 await readHeaderFooter(rntuple);
 
diff --git a/demo/node/simple.root b/demo/node/simple.root
new file mode 100644
index 0000000000000000000000000000000000000000..3f90a9da175cdca3229c136c5c5adeae7a1ff73d
GIT binary patch
literal 8511
zcmbW7Wl$YW*RF?+ySs;tL)bXMHxS&N;2MIvLxA8C+#$HTOMu``aCZn62o@wjfJ5@W
z&sXR9>ijyZs;j$adae7O?y326jg!5-3jq9@0|3Ab0H{Tt8~pQ_|GB|DH!-;9{uTfz
zKRow=&lmnb!w>fOIa9{7VO$#E{#*G^p=ZVa1iZTBI~#LU=XbUaHs&v#{&@P=1c3jO
z`8OK??4EPPp4)%3De(cA&QpG2Rd4LG7HhxH(f*yM|1JAZm-Sb@{%=0h|EO>O_qG|l
zs+f(v2>`rNgRugDdH`T(WP6~hM~4N#a4^qvr00dUo{BE6&*spd$Er$7>Qrt#FFAQ%
zLfAW>{_GPEAYt!nVq=c*JT}|JLkC1Jozy)%`CQSF&;T~1kP*Vf0H4<oGQ6dES1=k(
z2@bEZh3Ko;=dC6q{$q|(^xx)S-ai-m6aTllby7f-@~=4~QHsKKpe*yslot!jc7g~!
z5a)!Bz`VF-Wsj)r=zD}pV48^l%yjxd&v}jKVTjSh*g)Ccm#kiXG)3Ob;SgUaF(U#O
z0vm#XRKIF}wNwC!m>x$<p{<Ed{s$WLPo~FO@EvRAt1!;$!(w9nh(;8oh%a~5cf`n!
zPp}l&MUTy?PO-?n$$Xgln>-5^$_rg|9>?e`**j%MlmuvhMB*q3x_@wly9%32=XAdI
zT*$6KU2k(!po$c57B%2a2q5Z8`h4gVQR8_|wL_3hvs6o-LC?RQWR;rpk)|4hF@LZ}
zXm9udTtS>=*OK`#9hVk<w9Ib(*&!rd7z3%1#OgA~Zvn|7R`6hmn9qjoJ-d4C)z*wm
zWXLA^?Mk~fgJ57<fW~bbL;(dF(W$sM@1Ko~z=IK?k^4gcTuG!3|GSBKgbLE=bjL|a
z$QXWhtYGgnX(f%b>tj(Gq4d5nvRc~sa<r}fEfxE>VTYZwA_o#x7EPkN$zcLjfp6_n
zt}5mkSjxM*OiHiC16q*1Ee#r@jEDUxR;~TmZ`&2t?q-mUMD$NP%@9ezDfWnVgO(?m
z3W9fQ+!o>zm$mW2rFc`QW$6Mj{h4Q5k{Me<uth2taFXZgG>dIJbIa94=)cUP7lY<4
zUX#Z_9}e-8!~-NN8ioY#_)BNpI>M$b78Klr1d9BA+iGoKpqiackT9sCj5`?*;@71P
zehqd^5|xZBE_K*aSwhfCWXO9|<ENzFQti*MU>MCHAR@zH&S=^fYyVa$2tqnjjHvQ5
z-@z+sIgFS77BuV1#pLj5^;eBb@!Z1s0TNH#Pz-V7ah4<Ct&rJBSIiUAnE+BvOVD6o
zbIt#)>W|xdRh5U98N6t}OobL&_L)_S97VvzrR_YGhwRXS$-^*72CSAISX_*@Df{mA
z_+EvMIh2B=Ej#sBnC0b;uRJ5W)81^6Q2t%eK)?Mdv*!sDT8T`XwUMEGD=XH0F2rgg
zl}$qE)}QAg2_Qq87z3e@V4g+2yZF`dYOEk`S*HUzPHGQeSivTGu~M|%M}+>7?fzF`
z(%im!jeq>F4W{ghGsn%N^i&5^(JytMKhA5DfL;SD1-GzOM<T`DX9dzZLash5S0)Hc
zhUwcn>vd})njE59TbZko;lFWoyRX(c1HtN$hgyd^OjzDx;+jvhz!b_rMz_eZ92GZD
z`4<;|y~Pj;QNwEsoFwYP?`WJv+olb%WXhfC53J<@q#{vbF`YBqWhp98=wx1#l?B?}
zDR8!{WgT_{DPXUi<r!7YxTrNN!NUYL3{^A8o!l%Vom;{1?QT*P=Monq`6>sA5^lKY
zi7avMOqDfe`|Iie?AuQKiUDsZW?t-k#1k6lw-5`E+jx^an|`daU#j@@H#Fn{!@j;;
zgm=`V5|tJun)GhLwTHyFg;7juR`jB@MzO|1$9bl>s=XY9vs7Kk)Z6U_!yY`k@Lz->
zPJ6p%l9|ySCV^q2UYU6F@<PHK++~F5_{WY--D8}i>bAGCLtX_JG7J>X5_8Q32gAeK
zVY;RX3hzT}%sL9TVe0Y&e(+*HQBaLHK9nBHSqV>BLy-x}jr>urs*C&~eFV~JBod&Z
zixf%qaLt3VlQh-FNovs+OxX{c5wIMoE3)bOvL{9l$|-q;t*#Gy9A923v{tR`eGJgS
zWSc5}^GhJNOX4trgYm1~fNIAPaboP}Dqoz4%1NiDaOb5ciV<j_4NLSJ{?ApXccST+
z%-7fBu+wqdDzrFm`cGhkwT-CgVodMFdfb)apKoUS8nh7&?B0_ev?NOygyJBUJDUX|
zom%VS&f}#hJ)$P3(2Wjdks^8<Y!H2O!E_wVKy!{6q0%FkwlTR`KrHkjoABU~o#wJ{
zFOL4Pp}i4zTG@)~DGPg>0M%&ExnBE35WkzJIhIJ6uuVT4FL@rC7Yqo54GZNx6torZ
z-kADTNd%l@-<RVvRC1`Z+e;R>bXQt`R{Y7KL9OV&0jA+jS!(cg84h5vE>#gRs4L)r
z##2j~bC{Junde8}90c4{9<gQ5EuOSJ>g3MUG*?l|#Te@^TqQ6D?pnL{=8U>+M!cvx
zI&E-@##N8oH$<WQloK$EIRxOYN!~on$t_RI<0)sq1_A`~;F`+4bR@z(VsBg`vD&}4
zU8|E)DxsM5bnF)<j5k+hjaAH2zRtl?(QfvsC<+usc=>H&j}MzB5MWY5U&H-5seBRL
zB#kmF5&|-V?)fHh@LMps-F)8bBH8xfZWHg0J*v`uany<0q%2xU{<C3mFam1Kmqw29
z+M3!(pPSsW>pQ|l|2sV=q?Rgv5?ucpfuA;^fT;$hUqtQ=7<Do9RV++tkD~|+frus(
zuAYGoLXzTJ08i>;|F5sK+=8lIVfs@g?_`Uo_j`j~peClXexC<-aT(0MXE=pt`3V#0
ztBj;Y%t3J+3|Sdq4yYN}8cfWc>l6o8GAth|_4!$(`n%kfA}b}>bq9E}9ZVFM;~j*n
z$OQJkyJ;}dG_69LQ$`bwQ-4kUX2*eHqGYJmSCd4>(mOw>@d8<?+I*C`7_eNBQ0O{?
zDVdugtdnr1(sSvmNhjWo-BvA3NyLgXS*B<hnOw;+b^cjgf%k!_|H~?1C)iy=SB~gc
zk4~wPOy%v+2%=CBuwdtn>`rJf41;lU6#Y`eMbFdCC2NeL=pDzS{3UT8E|q}1g~B-?
z?O^5B%$;UTSUGH6d2hcsX9hi62|nJbmcepwmomh;Rz=UcHjdTFwB`DOh--pWLY#+;
z_QqsL1x#7c5tB|>b)4IOB}?lZv{5b1;&>2*xf;nWPP)Zk0#if@yADo)R|{%nA^=MV
z2~|raeCa}Km!wEH=+%J_zMIRZrZr3S%zg`v)JdYO!YrJ+S4oRvRnQ;R+7MqR_iI*C
z3~LsjA60;3Te16!*p3qIV<tHOpWi4e_;ZTsxEDEb#oRm>?nQHx1l(~bbnHBJnbnFU
zAMPfAG^(YO%y+Fabb4m#P1-MfJrVxF6c=z9$wnGHoN2;AY(0UMxlD7imkw%_^BHUu
zOfqYy5=n^4{q8ajET_gG=ko{fEqiV!nuZ6c21jg`Ox<@Md>(SEinyPYM}y!~8kXw`
zBjGwqrjDlQLL}sd=(B+*n%7RHvunXY;7GYFPhBgX_&NTA(iHRlgknJOS<kMhi*x*D
z-g{b(jdV0${5pNiZM}!r7QTy>hFPlRVX-0t*C0+oQTT@Bg&0L;O3<{#5?4LRn7mv`
zo8fc<p$e!e#(+$hLX*bPeQ-`KXuw#6GOY%eL7~Yz<Q<DIH-{)vLm(#PE%*J%Fo_g~
z(5hC)#0a1E)Mc_qhE|^#{}~w()%YkM$%NZ>lKS0XbbQZG`zn0LLfau6rn@VTMLNsi
zGy(ks*{sYUs`A=*8%EeLqTfC)j`N~jA!XON^)wl`RW(xeLi;Ff_rLdZik0Xu7~HZa
zn63J0tl!8R-~wmu5aG0$W~N4hzEuvnRGefLBR1<kWbsvUOtxaiho}I6&q>Mgox+jl
zr8)@;MD&-#4kv29>_PWIAh$|ZLceZ2G17`YZeIsiH}!X=Pzb)z6xS^a^T&9$I6>-d
z#jJD}iO_TxYV2%o9Q?k>E;LSz!GWS$<eKm)?TyAO2_gtyn0wVrYTr_2;`tC~zTCd>
zyuQ9qX$jF?2;o@H8!U>1X?r$vWisCvx%`NX2v40(NXUFm=mcfXGZ;dUG<1^Js$y^>
z39vRc<n;tidXW~hlUn@C(9oTe!_7t&qAA$qx{V&{u8Ia`-o@WPWJTCs6;X66Iw4Ur
z)pyw7al=+w)312kNjt%PGqL-96-H8XRr01n`JM7NM>&|z0?J`PMYS+?5ST{2nIJeb
z`VeJvQ=+P)XSk!lE6y&mSOAL_48!%!w3P(z7IqT$BDY1UZ@uq_`fYYNNQR`evy;)Q
zyA}bLEp!|X)QdIs4FN64^%o=vm6T*5r?-<qoQstApcbm5#h@Je+wmNf3NRV$v#e~J
z)j1yUE{SC(ZO;i?eGjbR0_ex+W234)owoupd+NQtJn<a#%Srn<avOfcdN24&w<8Uo
zpDiFtSea<e&c9F+{i5ht!C9ttZz^wdG<p?9hi|~rzKS1?fI4(t5iaI%ASu{twrI4P
zj3|5B%{O3)tnpBGkl%*Oo%kj1@IqpuPe4pPe34TVuPwong)G`MaMm_pPM0R=5sy7H
z>KKol2*=^ot4u5Ip2!K}IY^<^n%hF{)A@X(klF`x&E-oUZ8Ybk^?9@^bMTOFUQ#)l
z)Px5w6T;cO1lU~60ISfGFXn9EH2UQrNAxt)3)}ajgojFG=O=A?n`CB*^ApT>@g+RJ
zyy__tTlkkJ8TSTlLrC>xQ~DhT`VRMxo;ZlHpEQ3fQXMq1Cf_2P;jJ`=jUXp@Bev^p
zM~_65rt!XLn)oJY<UW8((}=`>-|J|Tv#z&DKoU_cGw^~vIEBZMoYRO1rTMNxB!#oc
zvd7crR!mDDEQw05{`D~dv(Gq?UAXFSU&~l6K7fzm=y$2KHiDq%d4V*`HKP7@U_Jc8
zD@Tha3}s@c<%atC0RD)<D*mq}r3`K9GRCIiLOHTd?x6Q)i`-JE9-6ltwj|V4^NaB|
zzmo=gzq10KXuC@o#cSn`!M&>TZq=fomCT*!WX9-viLj9RudCVtf#yf1U9a4@F@{Ek
z36+GC&Aib!9S-odEcvP9a0YrNA0|*5<gg+aztYO<SfuQ6B|}qSr0d>d;$zDO(MeB+
z@UiDsq0qj98#rDXhjW-M(7<w5W1!(xW^Q<(2SIcybL&$?7EZkOTv`reXk!^IP!u~k
z*n7iC@|~weAsPEQ9=DRtJ2>2mmJX#ouMIPU56U>&N-<bN%`3QCmqua|@6A8nD?pFT
zKDA*=!yxG;h=CjxYOf^o*g#g4<Ov40)nCGZp%BV_`eHJt?FJntw}lubL=&m}ma?R}
zCUzIw(?h(0v4@HdO}o)>Fs-6b1y%eo;Lx?oc@%*$HaxR(&c}{S+wC_$jQ`qX)%|@!
zz&Tc~#@K|Bok4K(3T*uBSd^j$<s>2&n9Qrop3uY8iD%MHi=MSdV4mZc>BrH#b{bYv
zs?Fa?jIqK+BwvJubAx2K<W3ByBm-+8mhd0o`X4#qzLb;IGrSa_W!AEcgngZKqUM#B
zyO|t5VP8A?smA1tEsh$_XV>@QMJ$=B2Ymm+$XBG#b0g@)6z8~BR$X|Ubl3eTdC5LH
zk~kSYV$|c;rq><<mAjnITh~1!F@6C&xAToz;!Bko<IsyaINjCb>?%@<IBvOwO~1nw
z?0gyf4+aL4-QyTANL4z6&_eP9Gh{X5x=EvrX;&W;`w_cEZf{Wpm`AQqK9D=*?YCMx
zMgj~&3^_h%SVR`WM~{3(M3&ZZ-^7n)Rp+yhMDR-{D07GeFC89<z+TxN+4lIKBP(uY
zDe++=yI&|MV@j@;EofeU+hTCA@s%1_Uw*j?ivUYUJJqu^h}^?3op|!Q9tlJ!Jxi~p
z{u3E(*ZN2IS?lh;Bt$z>+K>>|oL!vA>&TRqs&(F-C|}4zbU9X|LT-D_T?aH?CLX<K
zfi(AZ8E%yDW!y=Olb7|POe;N&Sulbu;&B!q*$qL#rr#opYtdLr`Dg%aW-&Zzam5wZ
zP8FeqPe%n-8Jus{s%J1}H2#rs>!e&GpS=1^^IoVqb*>~mu%=W@t2rGsMQ-#W)RSgA
zkxnt?{++7{WL?Jx+=4mQCZc+(G$(+M-8DO(eMgq86AtMhbB9y73|&beWmgakA6^|Z
z-!hZSat@L2ewjQ9n&o41o0!yoQK%wzzmzl7BElSb^7?J$1Q4@Yyo*O8`bjl^A)d9v
zbtrzD+`g$@dj7}GS9q5uk8)e*k3Xac!xDUqG`2H|mx~Ns0ydK2VtcXm*6Cj##|LCW
zJbqkmtu-43Z5Yiqd&RjTGaYo6;~=QDiGhS8=KOngE2{^YEa0#DRJWEle@X}s0F3Qc
zF^zd#2n&t2^@u02W{rJvVgWKQcG|MkaT%=fgDT5;YHNOd<NsAkg9V9T7h2*%nmt(!
zO!T5zOyWTg%g%_dXbn$)sc=;T<ED*;unrLvJuk7=e`{J{(1)?r_V%MXA<dVO&eqrJ
zlIl9Q!{`i#+DPv2@gPYdCgGv+h}#*W=p8bGfs43B9zRrRE;e65Jx1Vt#Xrkd-ib3{
zOQjF=vGI$B#;j;v?MP5bY_v=hntPqUmW^n$&jGBXUT>Z4gIs;z;-nkYJ4YVHPe2LR
zT;w=abCXoPRdxyh$=@I3OY8F0SU&lYfQ4uxD*F)`x}MTL7&#(?^7T2RL(GS;uNop=
ztqK}iBXj!P-V$YlA+#vf`*2;8^u>u&+@V~pC{<o&-AVH+U51sW!JjqwMlA6Xy)|ee
zCGN_a48{t?qQ4Us+)oK>n{ZY_-E+Pwz!Pc6K)wrC!t=Ac;SmY@eAkxW@_O%jJjVmD
zh`e9RD+vAwyo_VM>Sb!8s+UPDWJfjeZ)U}lx|Vh_A{E`nd((dg4Nr~mfsu34rh*3g
zJC=>KS)=;RMjGKV(4NvK2eWICIA(JN05jDj6fvn`T((m6V@IyamlBP;2i0}NkqgvM
ztJCtdDyEaY4*6zp)MX6ImMk~fm8S;vDQ%Fg#o1;Gnp_bfeNUHr{^}VA;hV-RSCTAJ
zHie;q>Nz!vZxT=jdQh1#e};dhZMksLK~)MNJ4oA3;{UY?I@`QSGi174qYmkAM4L>J
z^stU4?%S8MW<ss(@lpE9PW$nN*sy!s$5gb0j!$a1;`)rV`z0Wo3+YX_rzBNGg%4&C
z^cm|#PU7H)a(}SU{oa5yx^WB=uMLaeWZod-PDO)dONpazpsy(&u}PjwiDJ~AP|7@e
zq@_}n7gt(qD=Z=t1sT{uT$-K6I{ammxv=59y{p4;*5pSDLnU;%hcI!p-yF-)Uwb5S
z>;f_}IC7==b@>IXmT;nWQG$7YP~5KOF%%4mo4qFyXoB&_l}x$1&!uLa9^0xMh^(VH
z_;joM%Q4kojIgAf@^QKZw2*RBW@Pd0Kxfm*Wqv-30lS5x5w!&geROi>rQg87V1hG2
zjhOOohU<snM;TFe<<*ZR5-lki>yWOMuHB0%tO(x6J`cZhE6(_?%wM@VUg&xDbP0GC
zA)Xa9M@-EE*1fQa$GR7SVg#+eYYkD+<KzUj`NhFM%H_tSUr<5sET_<^nqyw@@{)*V
z!C~lgaYqC&n_;n@Mo`fim?sO*RRNJC?~R_!p}dmC2icT2V@Fbm4tJ@I87FBH9AHjZ
z8Le3qRDI}XXKE;Vj{WK~-col!#fF&YO_;Nm2u<T01F~tBK6DSV{8NMug31}3;JqNb
z&N3lXQ!lHU%oyHQZyRFJcqyTCQ4LquKwxbah6R#X5}NQ()t3r`n}y3BTl<7t$fWW9
zyMOKZvF0O0L^S|mWLa<ooMxYXh^U=QZ|GVN_5UiFQ~WOW(FZ{ESYoE0Z7)+08)<35
zC^OANCAe4&60E;BoRRh}k;uxN8=b=@R94mdDc`3QfKeTD^<8uFQuN>j%k&^OwKnxi
z(zxFQ!anF^d10{ptuYrkRfvW$l?b`_L=9DtuW`dn`!KEF57A@-Q$66JUhAyDUyG&#
zG~8s9DF>bUiH2x*B>LKR@n+tTlx54`Q&h464h@Z&RT%U7j0Qz4;YXAc*wVTVJ^9@$
z+ov*Gq*ea5ewp`nKBr`&P3W<OA3I^lZ6OAYtS&WzYj}hGi@>bhVGG1(2F$Xk9}RWL
z6KJyp?&hoOs8l#^HaH{YrKdhzebf1Bo*`BfE8B2py68-kh{hyB!%#U5G;jB^ob!tY
zGazbLOeB0pt8M9++)%2jp&1k5amUYV*fU+YuFsQJZgs%+S}R9Cu82t-hT$6$YazZ>
ze^sPh&P$RBml`xXX_ReIDd6Mmdsb?5D25?jf}!g#xdW>_BQ=2!0}FrrQ%TL!qG+s9
ztIo2{H0;h-Cw4T{5ibq)(<2rPJm#^nU7IcmL!yYYY}mkfb{Yh4mD0K<;+&jt31`QC
z?r1w|8;5-Lr5{eH$E}%keM7JG%-&;B^okPgY5+NYLt@sdYy3Vz(LtVRI{3X2PZygQ
zOKH#0{dgleezB>coC{IT=AIgXh>5TIi6To7Y3l3*NuL#b%*RBL#<?CVIgU~yEe5at
zSU%0m-P!V4t-ca0OM;}DoOKqh0{c-T{r=FDqdb37`9cEA0~G3BUO7^vgIX`ApO~B=
zlS&o2v|_`9*Nh>ZS0H!V3AJ2^Dff+!&-Jw%8o)eo2Rw|B$muJ`A`i)LJ&Ge&8hjsM
zWX=@){1mz%O9BtGV3;6J1;Tsfwy4PLe53n;MgIHpqw?hB?Af&6JQ!y_l_+8ZWn+65
zv%Wf%HHg)o(5R$f9NSyYWeM4B^!g>e6WLQvj;9R$vLe$!>xW&?l^Xloz7p3!uc=IR
ze7VrK^j86LCD>ph4CJ@*NT?`9Rx40Abct7pw8e<n5Rn*NBU7ahzMsY2_n(?-t4^}d
zM>%U|FO{><%GQjR$oD0+Guz}X9H;2?#xVAi-~I3<-G&b9MF?25FL(%NKb>5=8cctB
zpYFr6a<fv4R`lwSn2F-;%~?yQ!4&FEP#q^<6#IS)j2mwWzT|C_SUP9+%kS5x6#l`o
zOMG0n9$!bXI<rNPV)S=16hHehi;eZTW&V7XHj=X3!&N!cxUFT6qF%A;nDF6}C~}6Z
zCZK-T{!KjVgukSOP>Zvqz}qu>v9*j6a7bsye8X;-g#a}{MxXX>^ITwM-_`nwK}f_;
zPs&Ok7u$HV(|Nz_Q~!Kg0!~YITH{_3Pj^i(#Wl}C-Ml;fzM%$s@ottQZ~)`1MiU*2
zdZS8<(1mp|4-7=s*XprigZF~tq5Z(H0Ws2>m@t>e?bea4za0sg<P~<$;_L*4HR_1G
zxYS9or$`IFS(Ro&YP_8gV);pxVFrp5$!=2COl1InvBemXsl-8`Bj!xm8{bQ$g{$@0
z;?I03u=|(M5CL@g@(nZ@i<76ga(E-mPf8o3dM?#=d=Df77FK#*!mQE8ml`L(Y{ERt
z8BY4()}EBUG)4a?{BiGpMs$#=nvQ+bVpr2JEHvFvC*0ato3W1UJo@IVPYAEzPU|Uq
zrD?{2wxb|~Q8U7OC0Qk%p|aK;DWVl$OFiqhyREzHr0edCg+TsZjl=2Gs|mx8c%;Qv
zo{o1;xHnR0frE9qIb)c{SxP@k{|%i!)OCn5Bn!3J#wm@f%L3xveI__cx-;>OS|Lnv
zC(6l)1xJr~C5^ReRdDHTL6e2#r3v}LC3EfL+wH9|3^1`+e*>ubrMbBc&FCwU@1C^A
zsK>-264j0&OS-m$Cc2+v)!wtbb+bIZu((`xwfHqgRLe|(S%Zz+FoVu<%CRjwb|u_=
zzdoRc-+QI3VC{>$^^E=k{!&Yye}h5t)W2Bp-(XM?0DS&SEqz!)z$FOwdHxT7T>T3u
ziGTyxuCYa;-%n5bqySI~bNh@fk*s36=4GxNkN~Mzr0os~H+4K_B7{0Xf`AJ2EaUsv
zK;pj*P!Rt=49EgN;(rY!qJsbz5a@aSj{&~Rr@lXo6!L7rN9%deLoPD?4tuq)Bm)It
z%NJc&BGp8QN`POzR|R40q%Ca$*w2gJ{}osKE6)E9v!zJ>M;!eRgyrW~RaE~&Ws&~D
zvws+_AOJjX$X|x5m<0pCfkglCV$h!&Flc~tJ%u=+miT-PI2`_7!lre~hD7B*0}D0t
z*)-bY34Lp`8S{M4?ytP?UwOzs^3SOGKVkO2@brIR`TwWoKV<!n8r<GrHR=CRduHx`
z!wg<s{++W6nwpD~xv{OelZ>5(J<ea=>`7(w&d%E0?74Gxd46<u7+??XKZJM>RtOo0
zALrn9u%0IReOv!11rP!N_=YG7jyfa$#}Cpa$?0oltoHCiY8oxD>YQCeOKdM}kW7Y#
zrfxjwbU?%LK8Ko}q!7)Sx&k>ML@lmzK%ZkS$OkFig$wz2(!-E#%VH&qEHo%6n2!5r
znL3!AYGTT>M1y1mLs$T+#nU_jOO4r2K-W>%MrM7t;TX~1a?r}*xkRA~eBCswM9IUL
zI}eF}4~D{RksIrd*{~!_t7II~zWWfGAhhmar4ZUi<W#QNUv<<L!<(3l!S@XvmVs&$
z6c@MV@B&<*7f6Xz2G>qEt%|IgjK`UdMQ;i<3>+)PTi~h>B>qxlZIY|s&4OFyi2>=~
zD3CjvAsd{i>qqf;Nr|=x$6=9zRio)B#$pADlX`0+`09C=`Tw3b%D>P1@2?Plj^KZv
O_w%bnE#l6d2>c(FB@wy+

literal 0
HcmV?d00001


From ff2e65900b1d65898d3335703fe837685b1f0334 Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Fri, 27 Jun 2025 15:50:32 +0530
Subject: [PATCH 4/9] uncommented the code

---
 modules/rntuple.mjs | 52 ++++++++++++++++++++++-----------------------
 1 file changed, 26 insertions(+), 26 deletions(-)

diff --git a/modules/rntuple.mjs b/modules/rntuple.mjs
index ee8f4362c..0cf415522 100644
--- a/modules/rntuple.mjs
+++ b/modules/rntuple.mjs
@@ -497,14 +497,14 @@ const numRecordCluster = reader.readU32();
 }
 
 // Example Of Deserializing Page Content
-// deserializePage(blob) {
-//   const reader = new RBufferReader(blob);
-//   console.log('Deserializing first 10 double values from data page ')
-//   for (let i = 0; i < 10; ++i) {
-//     const val = reader.readF64();
-//     console.log(val);
-//   }
-// }
+deserializePage(blob) {
+  const reader = new RBufferReader(blob);
+  console.log('Deserializing first 10 double values from data page ')
+  for (let i = 0; i < 10; ++i) {
+    const val = reader.readF64();
+    console.log(val);
+  }
+}
 
 
 }
@@ -556,31 +556,31 @@ async function readHeaderFooter(tuple) {
                   throw new Error(`Unzipped page list is not a DataView, got ${Object.prototype.toString.call(unzipped_blob)}`);
 
                tuple.builder.deserializePageList(unzipped_blob);
-               return true;
+              
 
                // Read the first page data
-              //  const firstPage = tuple.builder?.pageLocations?.[0]?.[0]?.pages?.[0];
-              //  if (!firstPage || !firstPage.locator)
-              //     throw new Error('No valid first page found in pageLocations');
+               const firstPage = tuple.builder?.pageLocations?.[0]?.[0]?.pages?.[0];
+               if (!firstPage || !firstPage.locator)
+                  throw new Error('No valid first page found in pageLocations');
 
-              //  const pageOffset = Number(firstPage.locator.offset),
-              //        pageSize = Number(firstPage.locator.size),
-              //        uncompressedPageSize = 8000; 
-              //                     console.log('Compressed size :', pageSize);
+               const pageOffset = Number(firstPage.locator.offset),
+                     pageSize = Number(firstPage.locator.size),
+                     uncompressedPageSize = 8000; 
+                                  console.log('Compressed size :', pageSize);
 
-              //  return tuple.$file.readBuffer([pageOffset, pageSize]).then(compressedPage => {
-              //     if (!(compressedPage instanceof DataView))
-              //        throw new Error('Compressed page readBuffer did not return a DataView');
+               return tuple.$file.readBuffer([pageOffset, pageSize]).then(compressedPage => {
+                  if (!(compressedPage instanceof DataView))
+                     throw new Error('Compressed page readBuffer did not return a DataView');
 
-              //     return R__unzip(compressedPage, uncompressedPageSize).then(unzippedPage => {
-              //        if (!(unzippedPage instanceof DataView))
-              //           throw new Error('Unzipped page is not a DataView');
+                  return R__unzip(compressedPage, uncompressedPageSize).then(unzippedPage => {
+                     if (!(unzippedPage instanceof DataView))
+                        throw new Error('Unzipped page is not a DataView');
 
-              //        tuple.builder.deserializePage(unzippedPage);
+                     tuple.builder.deserializePage(unzippedPage);
 
-              //        return true;
-              //     });
-              //   });
+                     return true;
+                  });
+                });
             });
          });
       });

From 13f45a5842e462b291f5bf13c08bf6cf651fbf77 Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Fri, 27 Jun 2025 15:51:42 +0530
Subject: [PATCH 5/9] removed warnings

---
 modules/rntuple.mjs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/rntuple.mjs b/modules/rntuple.mjs
index 0cf415522..67ada3b4d 100644
--- a/modules/rntuple.mjs
+++ b/modules/rntuple.mjs
@@ -499,7 +499,7 @@ const numRecordCluster = reader.readU32();
 // Example Of Deserializing Page Content
 deserializePage(blob) {
   const reader = new RBufferReader(blob);
-  console.log('Deserializing first 10 double values from data page ')
+  console.log('Deserializing first 10 double values from data page ');
   for (let i = 0; i < 10; ++i) {
     const val = reader.readF64();
     console.log(val);

From a46c75b93593db69caa29fd3657e9a94d26e3773 Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Mon, 30 Jun 2025 14:18:52 +0530
Subject: [PATCH 6/9] Column Validation

---
 demo/node/rntuple_test.js |  8 ++++++--
 modules/rntuple.mjs       | 12 ++++++++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/demo/node/rntuple_test.js b/demo/node/rntuple_test.js
index 9ac5792bd..ffc968a3e 100644
--- a/demo/node/rntuple_test.js
+++ b/demo/node/rntuple_test.js
@@ -1,14 +1,18 @@
 import { version, openFile } from 'jsroot';
 
 import { readHeaderFooter } from 'jsroot/rntuple';
-
+import path from 'path';
+import { fileURLToPath } from 'url';
 
 console.log(`JSROOT version ${version}`);
 // const file = await openFile('https://jsroot.gsi.de/files/tmp/ntpl001_staff.root'),
 // rntuple = await file.readObject('Staff');
 
-const file = await openFile('./simple.root'),
+const __filename = fileURLToPath(import.meta.url),
+__dirname = path.dirname(__filename),
 
+rootFilePath = path.join(__dirname, 'simple.root'),
+file = await openFile(rootFilePath),
 rntuple = await file.readObject('myNtuple');
 
 await readHeaderFooter(rntuple);
diff --git a/modules/rntuple.mjs b/modules/rntuple.mjs
index 67ada3b4d..3b07e6e7f 100644
--- a/modules/rntuple.mjs
+++ b/modules/rntuple.mjs
@@ -538,6 +538,18 @@ async function readHeaderFooter(tuple) {
          tuple.builder.deserializeHeader(header_blob);
 
          tuple.builder.deserializeFooter(footer_blob);
+
+         // Column Validation
+const firstColumn = tuple.builder.columnDescriptors?.[0];
+if (!firstColumn)
+   throw new Error(' No column descriptor found');
+
+if (firstColumn.coltype !== 13)
+   throw new Error(` Expected column type 7 (kReal64), got ${firstColumn.coltype}`);
+
+const field = tuple.builder.fieldDescriptors?.[firstColumn.fieldId];
+console.log(`Field: ${field?.name ?? 'undefined'} | Type: ${field?.typeName ?? 'unknown'}`);
+
         // Deserialize the Page List Envelope
          const group = tuple.builder.clusterGroups?.[0];
          if (!group || !group.pageListLocator)

From c0068baddc56b219439a57b588e1a7510db3aca8 Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Mon, 30 Jun 2025 14:35:35 +0530
Subject: [PATCH 7/9] simple method to pass simple.root

---
 .github/workflows/jsroot-ci.yml | 7 ++++---
 demo/node/rntuple_test.js       | 9 +--------
 modules/rntuple.mjs             | 2 +-
 3 files changed, 6 insertions(+), 12 deletions(-)

diff --git a/.github/workflows/jsroot-ci.yml b/.github/workflows/jsroot-ci.yml
index 91248eeb4..1bbe109be 100644
--- a/.github/workflows/jsroot-ci.yml
+++ b/.github/workflows/jsroot-ci.yml
@@ -63,7 +63,7 @@ jobs:
           node demo/node/file_proxy.js multi ./hsimple.root
           node demo/node/file_proxy.js buffer ./hsimple.root
           node demo/node/buffer_test.js
-          node demo/node/rntuple_test.js
+          cd demo/node; node rntuple_test.js; cd ../..
 
   tests_ubuntu:
     runs-on: ubuntu-latest
@@ -177,7 +177,7 @@ jobs:
           node demo/node/file_proxy.js multi ./hsimple.root
           node demo/node/file_proxy.js buffer ./hsimple.root
           node demo/node/buffer_test.js
-          node demo/node/rntuple_test.js
+          cd demo/node; node rntuple_test.js; cd ../..
 
 
   build-windows:
@@ -226,5 +226,6 @@ jobs:
           node demo/node/file_proxy.js multi ./hsimple.root
           node demo/node/file_proxy.js buffer ./hsimple.root
           node demo/node/buffer_test.js
-          node demo/node/rntuple_test.js
+          cd demo/node; node rntuple_test.js; cd ../..
+
 
diff --git a/demo/node/rntuple_test.js b/demo/node/rntuple_test.js
index ffc968a3e..c7706001f 100644
--- a/demo/node/rntuple_test.js
+++ b/demo/node/rntuple_test.js
@@ -1,18 +1,11 @@
 import { version, openFile } from 'jsroot';
 
 import { readHeaderFooter } from 'jsroot/rntuple';
-import path from 'path';
-import { fileURLToPath } from 'url';
 
 console.log(`JSROOT version ${version}`);
 // const file = await openFile('https://jsroot.gsi.de/files/tmp/ntpl001_staff.root'),
 // rntuple = await file.readObject('Staff');
-
-const __filename = fileURLToPath(import.meta.url),
-__dirname = path.dirname(__filename),
-
-rootFilePath = path.join(__dirname, 'simple.root'),
-file = await openFile(rootFilePath),
+const file = await openFile('simple.root'),
 rntuple = await file.readObject('myNtuple');
 
 await readHeaderFooter(rntuple);
diff --git a/modules/rntuple.mjs b/modules/rntuple.mjs
index 3b07e6e7f..023e99aba 100644
--- a/modules/rntuple.mjs
+++ b/modules/rntuple.mjs
@@ -545,7 +545,7 @@ if (!firstColumn)
    throw new Error(' No column descriptor found');
 
 if (firstColumn.coltype !== 13)
-   throw new Error(` Expected column type 7 (kReal64), got ${firstColumn.coltype}`);
+   throw new Error(` Expected column type 13 (kReal64), got ${firstColumn.coltype}`);
 
 const field = tuple.builder.fieldDescriptors?.[firstColumn.fieldId];
 console.log(`Field: ${field?.name ?? 'undefined'} | Type: ${field?.typeName ?? 'unknown'}`);

From f688eddce842ecbf382ae5e54c836306be26c3ca Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Mon, 30 Jun 2025 15:00:30 +0530
Subject: [PATCH 8/9] Calculating the uncompressed Size

---
 modules/rntuple.mjs | 43 ++++++++++++++++++++++++++++++++++---------
 1 file changed, 34 insertions(+), 9 deletions(-)

diff --git a/modules/rntuple.mjs b/modules/rntuple.mjs
index 023e99aba..7f18ecf91 100644
--- a/modules/rntuple.mjs
+++ b/modules/rntuple.mjs
@@ -540,15 +540,34 @@ async function readHeaderFooter(tuple) {
          tuple.builder.deserializeFooter(footer_blob);
 
          // Column Validation
-const firstColumn = tuple.builder.columnDescriptors?.[0];
-if (!firstColumn)
-   throw new Error(' No column descriptor found');
+        const firstColumn = tuple.builder.columnDescriptors?.[0];
+        if (!firstColumn)
+           throw new Error(' No column descriptor found');
+        
+        if (firstColumn.coltype !== 13)
+           throw new Error(` Expected column type 13 (kReal64), got ${firstColumn.coltype}`);
+          const field = tuple.builder.fieldDescriptors?.[firstColumn.fieldId];
+        console.log(`Field: ${field?.name ?? 'undefined'} | Type: ${field?.typeName ?? 'unknown'}`);
+
+        // Returns the size in bytes of one value based on its type
+        function getElementSize(typeName) {
+           switch (typeName) {
+              case 'double': return 8;
+              case 'float': return 4;
+              case 'int32_t':
+              case 'uint32_t': return 4;
+              case 'int64_t':
+              case 'uint64_t': return 8;
+              case 'int16_t':
+              case 'uint16_t': return 2;
+              case 'bool':
+              case 'uint8_t':
+              case 'int8_t': return 1;
+              default:
+                 throw new Error(`Unknown type for uncompressed page size: ${typeName}`);
+           }
+        }
 
-if (firstColumn.coltype !== 13)
-   throw new Error(` Expected column type 13 (kReal64), got ${firstColumn.coltype}`);
-
-const field = tuple.builder.fieldDescriptors?.[firstColumn.fieldId];
-console.log(`Field: ${field?.name ?? 'undefined'} | Type: ${field?.typeName ?? 'unknown'}`);
 
         // Deserialize the Page List Envelope
          const group = tuple.builder.clusterGroups?.[0];
@@ -577,7 +596,13 @@ console.log(`Field: ${field?.name ?? 'undefined'} | Type: ${field?.typeName ?? '
 
                const pageOffset = Number(firstPage.locator.offset),
                      pageSize = Number(firstPage.locator.size),
-                     uncompressedPageSize = 8000; 
+
+                  // Calculate the uncompressed page size in bytes using element type size and number of elements
+                   elementSize = getElementSize(field?.typeName ?? ''),
+                   numElements = Number(firstPage.numElements),
+                    uncompressedPageSize = elementSize * numElements;
+                 console.log(`Uncompressed page size: ${uncompressedPageSize}`);
+
                                   console.log('Compressed size :', pageSize);
 
                return tuple.$file.readBuffer([pageOffset, pageSize]).then(compressedPage => {

From 9a75e5fcff20fcf70d91c18379f6d150cca6d018 Mon Sep 17 00:00:00 2001
From: Krmjn09 <mahajankriti672@gmail.com>
Date: Mon, 30 Jun 2025 16:04:14 +0530
Subject: [PATCH 9/9] suggeted changes

---
 modules/rntuple.mjs | 49 +++++++++++++++++++++++----------------------
 1 file changed, 25 insertions(+), 24 deletions(-)

diff --git a/modules/rntuple.mjs b/modules/rntuple.mjs
index 7f18ecf91..2e08d9355 100644
--- a/modules/rntuple.mjs
+++ b/modules/rntuple.mjs
@@ -497,13 +497,20 @@ const numRecordCluster = reader.readU32();
 }
 
 // Example Of Deserializing Page Content
-deserializePage(blob) {
-  const reader = new RBufferReader(blob);
-  console.log('Deserializing first 10 double values from data page ');
-  for (let i = 0; i < 10; ++i) {
-    const val = reader.readF64();
-    console.log(val);
-  }
+deserializePage(blob, columnDescriptor, fieldDescriptor) {
+   const reader = new RBufferReader(blob);
+
+   // Validate the column type before decoding
+   if (columnDescriptor.coltype !== 13)
+      throw new Error(`Expected column type 13 (kReal64), got ${columnDescriptor.coltype}`);
+
+   console.log(`Field: ${fieldDescriptor?.fieldName ?? 'undefined'} | Type: ${fieldDescriptor?.typeName ?? 'unknown'}`);
+   console.log('Deserializing first 10 double values from data page');
+
+   for (let i = 0; i < 10; ++i) {
+      const val = reader.readF64();
+      console.log(val);
+   }
 }
 
 
@@ -539,15 +546,12 @@ async function readHeaderFooter(tuple) {
 
          tuple.builder.deserializeFooter(footer_blob);
 
-         // Column Validation
+         // Extract first column and corresponding field
         const firstColumn = tuple.builder.columnDescriptors?.[0];
         if (!firstColumn)
-           throw new Error(' No column descriptor found');
-        
-        if (firstColumn.coltype !== 13)
-           throw new Error(` Expected column type 13 (kReal64), got ${firstColumn.coltype}`);
-          const field = tuple.builder.fieldDescriptors?.[firstColumn.fieldId];
-        console.log(`Field: ${field?.name ?? 'undefined'} | Type: ${field?.typeName ?? 'unknown'}`);
+          throw new Error('No column descriptor found');
+
+        const field = tuple.builder.fieldDescriptors?.[firstColumn.fieldId];
 
         // Returns the size in bytes of one value based on its type
         function getElementSize(typeName) {
@@ -589,21 +593,19 @@ async function readHeaderFooter(tuple) {
                tuple.builder.deserializePageList(unzipped_blob);
               
 
-               // Read the first page data
+               // Access first page metadata
                const firstPage = tuple.builder?.pageLocations?.[0]?.[0]?.pages?.[0];
                if (!firstPage || !firstPage.locator)
                   throw new Error('No valid first page found in pageLocations');
 
                const pageOffset = Number(firstPage.locator.offset),
                      pageSize = Number(firstPage.locator.size),
+                     elementSize = getElementSize(field?.typeName ?? ''),
+                     numElements = Number(firstPage.numElements),
+                     uncompressedPageSize = elementSize * numElements;
 
-                  // Calculate the uncompressed page size in bytes using element type size and number of elements
-                   elementSize = getElementSize(field?.typeName ?? ''),
-                   numElements = Number(firstPage.numElements),
-                    uncompressedPageSize = elementSize * numElements;
-                 console.log(`Uncompressed page size: ${uncompressedPageSize}`);
-
-                                  console.log('Compressed size :', pageSize);
+               console.log(`Uncompressed page size: ${uncompressedPageSize}`);
+               console.log(`Compressed page size: ${pageSize}`);
 
                return tuple.$file.readBuffer([pageOffset, pageSize]).then(compressedPage => {
                   if (!(compressedPage instanceof DataView))
@@ -613,8 +615,7 @@ async function readHeaderFooter(tuple) {
                      if (!(unzippedPage instanceof DataView))
                         throw new Error('Unzipped page is not a DataView');
 
-                     tuple.builder.deserializePage(unzippedPage);
-
+                    tuple.builder.deserializePage(unzippedPage, firstColumn, field);
                      return true;
                   });
                 });