Add Postman Collection v2.1 export command

[vedssharma]

Adds apicli export postman to convert stored requests to a Postman
Collection JSON file that can be imported directly into Postman.

Supports three modes:

• Export all collections (default)
• Export a specific collection: --collection
• Export request history: --history

Output goes to stdout by default; use --output to write to a file.
URLs are fully parsed into Postman's structured format (protocol, host,
path segments, query params). Request bodies are auto-detected as JSON.

https://claude.ai/code/session_01PyL8EW4HoiuaCszqviyfGt

[claude]

PR Review: Add Postman Collection v2.1 export command

Overall the implementation is clean and well-structured. Good separation of concerns across the builder functions, proper error handling with os.Exit(1), and correct use of 0600 permissions for the output file. A few issues worth addressing before merging:

---

Bugs / Correctness

1. --collection and --history flags are not mutually exclusive

Both flags can be passed simultaneously (--collection foo --history). The if/else if/else chain silently picks --history first. Either make them mutually exclusive or document the precedence:

if collectionName != "" && exportHistory {
    format.PrintError("--collection and --history are mutually exclusive")
    os.Exit(1)
}

2. isJSON is a syntactic heuristic, not validation

Strings like {invalid json here} pass the check and will be tagged language: json in the export, which may confuse Postman's editor. Consider using json.Valid():

func isJSON(s string) bool {
    return json.Valid([]byte(strings.TrimSpace(s)))
}

3. All collections are flattened in buildPostmanFromAllCollections

When exporting multiple collections, all requests are merged into a single flat list — collection names are lost. Postman v2.1 supports folder items ("item" can contain nested "item" arrays). This would preserve structure:

type postmanItem struct {
    Name    string         `json:"name"`
    Request *postmanRequest `json:"request,omitempty"`  // nil for folders
    Items   []postmanItem   `json:"item,omitempty"`      // non-nil for folders
}

Then each collection becomes a folder item containing its requests.

---

Code Quality

4. Use Bool instead of BoolP for flags without a shorthand

BoolP("history", "", false, ...) passes an empty string as the shorthand, which is unconventional. Use Bool for flags with no shorthand:

postmanCmd.Flags().Bool("history", false, "Export request history instead of collections")

5. Non-deterministic header ordering

Iterating over map[string]string in buildPostmanRequest produces different header orderings on each run. For reproducible exports, sort the keys:

keys := make([]string, 0, len(headers))
for k := range headers { keys = append(keys, k) }
sort.Strings(keys)
for _, k := range keys {
    pHeaders = append(pHeaders, postmanHeader{Key: k, Value: headers[k]})
}

6. buildPostmanFromAllCollections name-selection logic is surprising

The logic that picks the single collection's name when there's exactly one collection (if len(collections.Collections) == 1) requires a loop to extract it. A cleaner approach would be to always use "apicli Export" or let the caller name it, since this is the "all collections" path.

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Test Coverage

No tests are included. At minimum, consider adding unit tests for:

• parsePostmanURL — especially edge cases: URLs with no path, query params, no scheme, unparseable input
• isJSON — valid JSON, invalid JSON, empty string, JSON arrays
• buildPostmanFromCollection with a nil collection result
• The mutual-exclusion flag validation once added

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Minor

• The Schema URL string "https://schema.getpostman.com/json/collection/v2.1.0/collection.json" is repeated in three places — extract it as a constant.
• items := make([]postmanItem, 0) in buildPostmanFromAllCollections could preallocate by counting total requests across collections, though this is trivial at CLI scale.